Primary vesicoureteric reflux in neonates with imperforate anus.

Cystography, performed in 26 out of a total of 33 consecutive neonates with imperforate anus, revealed primary vesicoureteric reflux in 12 cases. The reflux was usually pronounced, and was particularly common in females and in infants with urinary tract infections. The incidence of reflux was unrelated to the severity of the anorectal anomaly, and reflux was often demonstrated in patients in whom an intravenous pyelogram had shown an undilated upper renal tract.